Surveying instrument



SURVEYING INSTRUMENT Filed May 6, 1938 2 Sheets-Sheet l Eignl INVENTOR. A. N. BRuNsoN ATTORN A. N. BRUNSON 2,208,014

SURVEYING INSTRUMENT Filed May 6, 1938 2 Sheets-Sheet 2 A. N. BRu/vswv A a m w w W8 7% l N- m /f //z I a /&

. 1% p w W a I *iIllIIIIlll July 16, 1940.

Patented July 16, 1940 UNITED STATES 6 Claims.

This invention relates to improvements in surveying instrument.

The general object of the invention is to provide an improved surveying instrument having Q novel features of construction which provide greater accuracy than is obtainable with former levels. r p

A further object of the invention is to provide a novel support for the telescope of a surveying ll) instrument.

Another object of the invention is to provide an improved surveying instrument wherein the spindle is mounted in anti-friction bearings.

Another object of the invention is to provide *1 an improved surveying instrument wherein the base, spindle and socket are dust-proof.

Another object of the invention is to provide an improved surveying instrument which may be operated with accuracy at low temperatures.

Another object of the invention is to provide an improved surveying instrument wherein the base will not interfere with the spindle accuracy irrespective of howtight the leveling screws may 1 be tightened.

25 Another object of the invention is to provide an improved surveying instrument with a base designed so as to remain accurate irrespective of expansion and contraction of metals.

Another object of the invention is to provide 30 an improved surveying instrument wherein the base may be disassembled and give access to the clamps and leveling screws and, at the same time, the spindle and socket will remain in a sealed unit.

'35 Another objectof the invention isto provide an improved surveying instrument wherein in revolving the instrument, the vial remains in center and makes reading instantaneous.

Other objects andvthe advantages of this invention will be apparent from the following description taken in connection with the accompanying drawings, wherein:

'Fig. 1 is a side View of a surveying instrument embodying the features of my invention;

45 Fig. 2 is an enlarged section taken on line 2--2 of Fig. 1; I

Fig. 3 is a section taken on line 3-3 of Fig. 2 on a reducedscale; and

Fig. 4 is a view similar to Fig. 2 showing a 5 modification of my invention.

m In the accompanying drawings I have shown y invention as embodied in an instrument which i is indicated generally at E0 and I have shown my invention as embodied, for example, ina stand- W66 a d type of leveling instrument I2 mounted on member 2 l.

SURVEYING INSTRUMENT Amber N. Brunson, Kansas City, Mo.

Application May 6, 1938, S erial No. 206,422

the base 10. The instrument [2 includes the usual telescope l3 supported on a level bar M which includes a threaded socket portion l5.

As shown the base It! includes a foot plate It on which a leveling screw base H is supported by a plurality of leveling screws l8. Each of the leveling screws I8 includes an enlarged head l9 having a threaded portion thereabove and a depending portion which terminates in a ball.

tions 2! fits in a socket 22 of a foot member 23 which engages the foot plate l6. Opening through the under face thereof the leveling screw base has a plurality of apertures 24 therein in which threaded bushings 25 are positioned to 1 receive the threaded portion 20 of the leveling screws 18. The leveling screw base I! has a cavity 26 therein and therebelow a central recess 2'! which opens into the cavity 26. The leveling screw base 20 I! has a central upwardly projecting hub 28 thereon having an aperture 29 therein. Depending therefrom the leveling screw base includes a hub portion 30 having an aperture 3| there in the upper end of which opens into the recess 21. The 25 hub 30 has-an enlarged recess 32 opening through the lower face thereof which communicates with the aperture 3|.

The foot plate 16 includes a reduced upstanding central hub portion 33 and has a threaded 3o recess 34 therein opening through its lower face. The hub portion 33 has a recess 35 therein which opens intothe threaded recess 34 and a socket aperture 36 having "semi-spherical side walls opening into the recess 35. 35

Mounted on the leveling screw base I! I provide a spindle housing 31. As shown the spindle housing 31 includes an intermediate flange portion 38 and a downwardly extending portion 39 which is positioned in the aperture 3| and includes a protruding threaded portion 40.

Above the flange 38 the housing 31 includes a reduced cylindrical portion 4| having an enlarged head portion 42 thereon. Opening through the upper end thereof the housing head 42 has a recess 43 therein which forms a shoulder 43' and opening through the lower end the housing portion 39 has a recess 44 therein which forms a shoulder 44. The housing 31 has a central aperture 45 therein which at the upper end opens 5Q into the recess 43 and at the lower end opens into the recess 44;

Positioned in the head recess 43 I provide an anti-friction bearing 46 of the dust-proof type and positioned in the lower recess 44 I provide Each of the leveling screw ball porlo a similar anti-friction bearing il. Each of the bearings 46 and ll is shown as of the radial thrust type and includes an inner and an outer element the upper bearing being preferably larger than the lower bearing.

Mounted on the threaded portion ill of the housing El I provide a nut 48 which includes a reduced portion 8 to be positioned in the recess 32 of the hub 36. The nut 48 is adapted to be tightened against the face of the hub 39 until the lower face of the housing flange 38 is drawn into tight engagement with the bottom of the recess 21 to firmly secure the bearing housing Bl to the leveling screw base Ill. Positioned on the threaded portion id of the bearing housing below the nut 48 and Within the foot plate recess 35 I provide a nut member :39 having a semi-spherical surface engaging the foot plate aperture 36.

Positioned in the aperture 45 of the bearing housing Bl I provide a spindle member 50. Adjacent the lower end thereof the spindle includes a cylindrical portion 5! in which the inner element of the anti-friction bearing 41 is disposed so that this element is adjustable along the portion 55 of the spindle. Below the portion 5f the spindle includes athreaded portion 52 on which nuts 53 are positioned.

Adjacent the upper end thereof the spindle includes a-cylindrical portion 54 which is positioned in the anti-friction bearing 46; abovelthe portion 54 the spindle includes an enlarged flangeportion 55. Above the flange 55 the spindle includes a threaded portion 56 and thereabove a reduced centering dowel portion 51.

When the spindle 59' is operatively assembled in the bearing housing 31 the spindle flange 55 directly engages the upper face of the inner racewayof the bearing 48 and the nuts 53 are tightened into engagement with the inner raceway of the bearing ll! therebytightly clamping the outer raceway of the bearing 46 in engagement with the bottom of the recess 43 and the outer raceway of the bearing 41 into engagement with the bottom of the recess 44 thereby. firmly retaining the spindle 50 in correct aligmnent in the bearing housing 37.

An externally threaded dust cap 58 engaging a similarly threaded portion 59.0f the housing recess M is preferably provided on the lower cess M.

Mounted on the spindle 50 I provide a housing ring iii which includes areduced depending hub portion 65 and an upwardly extending reduced threaded hub 62.

The housing ring engagesa chemically treated felt washer lila which also engages the upper bearing :6 to provide a dust-proof seal. At the base of the hub portion 6i the housing ring includes a downwardly facing shoulder 6!". The housing ring 6i] when tightened engages the flange 55 and forces this flange against the inner end of the housing portion 39 to close the reelement of the bearing lfi and thus causes the outer. element of the bearing 46 to engage the shoulder A3 so that the upper bearing is held tight while the inner elementof the lower bearing is adjustable along the portion 5! so that when the nuts 53 are tightened the inner element of the lower bearing is moved towards the upper bearing and the pressure thus produced removes any film of oil which will have a tendency to cause inaccuracy.

My construction prevents shifting of centers due to any oil film on the shoulders or on the bearing and I find that-I can seccure an accuracy the former to within three seconds of arc. Due to this construction all particles of sand, dust, etc., are kept from the socket and spindle so that the life of the instrument is lengthened. The ability to tighten the bearing by holding the outer elements thereof fixed and pulling the inner elements together insures greater accuracy since it furnishes the desired metal-to-metal contact without wear. This construction also assures removal of all vertical and horizontal play in the bearings and thus accuracy is secured and maintained. Further my construction allows free use of, the instrument at temperatures well below zero degrees Fahrenheit at which temperature tapered bronze spindles either freeze or become so stiff that turning the spindle throws the instrument off the perfect horizontal plane.

The tapered bronze spindles do not contract as much in cold Weather as the housing in which they operate. This causes the instrument to become very stiff in revolving. Also the higher temperatures cause the spindle housing to expand more than the spindle and this causes a looseness. In my construction the expansion and contraction of metal does not interfere with the accuracy nor does it interfere with the rotating of the spindle When an objectivellens is extended out the full length it throws more weight on one end of the barrel than it does on the other. Other instruments have to be readjusted with the level,- ing screws to bring the level vial back in center while my instrument remains in the perfect horizontal plane because I have sufficient strength in the bearings and the ability to hold the upper and lower shoulders in metal-to-metal contact and have sufficient strength in the lower assembly to support the overhang or added weight caused by running the telescope slide in and out.

Other instruments have a looseness between the spindle and housing for a film ,of oil in or,- der. to turn the spindle freely. In revolving the instrument this looseness causes the vial to run from. one end to the other. An engineer is required to wait until the vial comes to rest before taking his reading. My instrument has no film of oil on the shoulder contact and therefore the tapered portion does not engage the housing. With this method of construction I am able to revolve the spindle while the vials remain in perfect center so that the reading is instantaneous.

Opening through the bottom thereof the hub 6! has a recess '63 therein and opening through the top thereof the threaded hub 62 has a thread ed aperture 64 therein which opens into the recess 63. The housing head is positioned in the housing ring recess 63 :and the threads of the threaded spindle hub 56 engage the threads of the threaded housing ring aperture 64.

Surrounding the housing ring hub "6! between the leveling screw base hub 28 and the housing ring shoulder 6! I provide a clamp ring 65 having a pair of spaced finger members 66 and 5'! projecting outwardly therefrom which are positioned one at each side of an upstanding lug 68 on the leveling screw base 11. The finger 66 includes an enlar'ged internally threaded boss 69 in which an adjusting screw member 10 is.positioned and which is adapted to engage one side of thelug 68. The other finger 61 includes an enlarged boss portion ll having a chamber 12 therein in which a spring pressed plunger 13 is positioned and which is adapted to engage the portion has a threaded portion I01.

face of the lug 68 opposite the screw I0. The outer diameter of the hub portion 6! of the housing ring is smaller than the diameter of the aperture 29 so that a space I3 is provided into which dust falls to keep the clamping ring free from grit.

At approximately one hundred and thirty five degrees from the fingers 06 and 61 the clamping ring 65 has a recess M therein opening through the inner face thereof and has a threaded aperture I5 opening into the recess in the recess 14 and through the extremity of the ring. Positioned in the recess 74 I provide a clamping shoe I6 and positioned in the threaded aperture I provide a clamping screw 11. When the clamping screw TI is tightened it forces the clamping shoe 76 into tight engagement with the housing ring 60 thereby firmly clamping the housing ring 60 and the clamp ring 65 together. Thereafter any slight adjustment of the housing ring 60 may be accomplished by manipulating the adjusting screw 10.

The instrument I2 is mounted on my improved base I in the same manner as is customary with the usual type of base, that is the threaded hub 62 of the housing ring 00 is positioned in a similarly threaded aperture 18 of the level bar socket l with the centering dowel 51 positioned in a suitable recess 19 in the level bar socket I5.

In use the device I0 is adapted to be mounted on a standard type of tripod (not shown) and secured to the threaded boss of the tripod head by the foot plate threads 34.

In Fig. 4 I have indicated my engineers level, which embodies a modified form of my invention, generally at 00. The level 80 as shown includes a level bar BI which like the level bar shown in Fig. 1 supports a telescope sighting member not shown. The level 80 further includes a leveling screw base 82 which is supported by a plurality of leveling screws 83 on a foot plate 84 and is swivelly connected to the foot plate 84 in the usual manner by a semispherical member 85 thereon engaging a com- I panion seat portion 80 of the foot plate.

The leveling screw base 82 has the usual central vertical downwardly convergent aperture 8'! therein to receive a spindle. The level bar 8I includes a socket portion 88 having a threaded recess 89 therein with a reduced centering recess I00 opening through the bottom thereof. According to my invention I provide an upper spindle anti-friction bearing IM and a lower spindle anti-friction bearing I02 which are positioned in the tapered aperture 81. The outer cages of the bearings NH and I02 are tapered to conform to the taper of the aperture 81 and are of a diameter to fit one adjacent the upper end of the aperture and one adjacent the lower end thereof.

In the aperture 01 I arrange a spindle member I03 having a lower reduced portion I05 and an upper reduced portion I06. The lower portion I05 has a threaded portion I06 and the upper Nuts I08 engage the threaded portion I06 while a nut member I09 engages the threaded portion I01. The nut member I09 has external threads IIO engaging the threaded recess 89 and a reduced hub III engaging the centering recess I00. In use the device is mounted in the usual manner on a standard type of tripod.

From the foregoing description it will be apparent that I have invented a novel surveying instrument wherein the telescope element remains accurate under all conditions of use and where there are few parts employed.

Having thus described my invention I claim:

1. In a surveying instrument, a leveling screw base having an aperture, a bearing housing on said leveling screw base and extending through said aperture, a spindle member positioned in said housing, an anti-friction member engaging each end of said housing, means on the upper end of said spindle engaging one of said members, means at the other end of the spindle engaging the other member, a housing ring on said spindle, said ring having a skirt disposed in said aperture, said skirt having a diameter less than that of said aperture to provide an annular dirt receiving slot, and a clamp engaging said base and said ring.

2. In a surveying instrument, a foot plate, a hollow bearing housing having an internal shoulder at one end and mounted on said foot plate, said bearing housing having a flange thereon, a leveling screw base about said housing, said base having a recess, said flange being disposed in said recess, said housing having a boss, means engaging said bearing housing and said boss to hold said leveling screw base against the flange, a flange spindle in said housing, an ainti-friction member engaging said spindle and said internal shoulder, a housing ring on said spindle, the lower .end of said bearing housing having an internal shoulder, a second anti-friction member engaging said last mentioned shoulder and said spindle, and means on the lower end of said spindle engaging the second anti-friction member.

3. In a surveying instrument, a leveling screw base having a cavity therein and having a central recess opening into the cavity, said base having a depending apertured hub, a spindle housing mounted in said leveling head and having an intermediate flange engaging the bottom wall of said recess, said spindle housing having a threaded lower end, a nut engaging said threaded end and said depending apertured hub, a housing ring having a recess, said spindle housing having a head fitted in said housing ring recess, said spindle housing having an internal, outwardly facing, shoulder adjacent each end thereof, a spindle in said housing, a bearing engaging each shoulder and means on the spindle engaging each of the bearings.

4. In a surveying instrument, a foot plate, a hollow bearing housing having an internal shoulder at one .end and mounted on said foot plate, said bearing housing having a flange thereon, a leveling screw base about said housing, said base having a recess, said flange engaging the end wall of said recess, said housing having a boss, means engaging said bearing housing and said boss to hold said leveling screw base against the flange, a flanged spindle, an anti-friction member engaging said spindle and said internal shoulder, a housing ring on said spindle and having a skirt surrounding the upper end of saidbearing housing, the lower end of said bearing housing having an internal shoulder, a second anti-friction member engaging said last mentioned shoulder and said spindle, and means on said spindle engaging the second anti-iriction member.

5. In a surveying instrument, a leveling screw base having a cavity-therein and having a central recess opening into the cavity, said base having an upwardly projecting apertured hub thereon and having a depending apertured hub, a spindle housing mounted in said leveling head and having an intermediate flange engaging the ill) bottom wall 015 said recess, said spindle housing having a threaded lower-end, a nut engaging said threaded end and said depending apertured hub, a; housing ring having arecess, said housing ring having a flange disposed above said upwardly projecting hub, and having a depending hub portion disposed within said upwardly projecting hub, said spindle housing having a head fitted in said housing. ring recess, said spindle housing having an. internal outwardly facing, shoulder adjacent each end thereof, a spindle in said housing, a bearing engaging each shoulder and means on. the spindle engaging each of the bearings,

6-. In a surveying instrument, a foot plate, a hollow bearing housing having an internal shoulder at one end and mounted on said foot plate, said bearing housing having a flange thereon, a leveling screw base about said housing, said base having a recess, said flange engaging the end wallv of said recess, said housing having a boss, a nut threadedly engagingsaid bearing housing and engaging said boss to hold said leveling screw base against the flange, a flanged. spindle, an anti-friction member engaging said spindle and said internal shoulder, a housing ring on said spindle and having a skirt surrounding the upper end of said bearing housing, the lower end of said bearing, housing having. an internal shoulder, a second anti-friction member engaging said last mentioned shoulder and said spindle, the lower endof said spindle being. threaded and having a nut thereon: engaging said second anti-friction member, and a dust cap engaging the lower end of said bearing housing.

AMBER Ni BRUNSON. 

